Spring diet of ringed seals (Phoca hispida) from northwestern Spitsbergen, Norway     

Labansen  Aili L.; Lydersen  Christian; Haug  Tore; Kovacs  Kit M. 《ICES Journal of Marine Science》2007,64(6):1246-1256

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Baltic cod recruitment - the impact of climate variability on key processes   总被引：3，自引：0，他引：3  

Koster  Friedrich W.; Mollmann  Christian; Hinrichsen  Hans-Harald; Wieland  Kai; Tomkiewicz  Jonna; Kraus  Gerd; Voss  Rudiger; Makarchouk  Andrei; MacKenzie  Brian R.; St. John  Michael A.; Schnack  Dietrich; Rohlf  Norbert; Linkowski  Tomasz; Beyer  Jan E. 《ICES Journal of Marine Science》2005,62(7):1408-1425

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细角滨对虾的幼体发育及形态特征     

许尤厚  胡超群  张吕平  陈国良  吴立峰 《热带海洋学报》2007,26(6):40-45

以细角滨对虾Litopenaeus stylirostris为实验对象,按时间顺序观察了胚胎各期的形态特征。通过解剖从无节幼体到仔虾第1天各期幼体的附肢,对其发育形态及其刚毛着生方式进行了描述和统计。比较研究了细角滨对虾和凡纳滨对虾L.vannamei无节幼体期形态差异以及色素的变化、溞状幼体期眼上棘形态的差异以及大颚齿数目。结果表明,无节幼体期细角滨对虾的色素明显多于凡纳滨对虾;两者溞状幼体期眼上棘的形态存在明显差异;两者在无节幼体至仔虾第1天各期大颚活动齿的数目变化一致。  相似文献   

On the longitudinal distribution of the solar surges     

Atίla Özgüç 《Solar physics》1989,123(2):381-383

After re-examination of data presented by Verma (1984), some misuse of solar parameteres published in Solar Geophysical Data is presented. Consequently some conclusions made by Verma (1984, 1986) on about the longitudinal distribution of cool solar surges based on these misuses are discussed.  相似文献   

Discrimination of floor cover of dry deciduous forest using Hyperion (EO-1) data     

Binal Christian  N. S. R. Krishnayya 《Journal of the Indian Society of Remote Sensing》2008,36(2):137-148

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Efficient GOCE satellite gravity field recovery based on least-squares using QR decomposition   总被引：3，自引：0，他引：3  

Oliver Baur  Gerrit Austen  Jürgen Kusche 《Journal of Geodesy》2008,82(4-5):207-221

We develop and apply an efficient strategy for Earth gravity field recovery from satellite gravity gradiometry data. Our approach is based upon the Paige-Saunders iterative least-squares method using QR decomposition (LSQR). We modify the original algorithm for space-geodetic applications: firstly, we investigate how convergence can be accelerated by means of both subspace and block-diagonal preconditioning. The efficiency of the latter dominates if the design matrix exhibits block-dominant structure. Secondly, we address Tikhonov-Phillips regularization in general. Thirdly, we demonstrate an effective implementation of the algorithm in a high-performance computing environment. In this context, an important issue is to avoid the twofold computation of the design matrix in each iteration. The computational platform is a 64-processor shared-memory supercomputer. The runtime results prove the successful parallelization of the LSQR solver. The numerical examples are chosen in view of the forthcoming satellite mission GOCE (Gravity field and steady-state Ocean Circulation Explorer). The closed-loop scenario covers 1 month of simulated data with 5 s sampling. We focus exclusively on the analysis of radial components of satellite accelerations and gravity gradients. Our extensions to the basic algorithm enable the method to be competitive with well-established inversion strategies in satellite geodesy, such as conjugate gradient methods or the brute-force approach. In its current development stage, the LSQR method appears ready to deal with real-data applications.  相似文献   

Mirdita Zone ophiolites and associated sediments in Albania reveal Neotethys Ocean origin   总被引：1，自引：1，他引：0  

Hans-Jürgen Gawlick  Wolfgang Frisch  Lirim Hoxha  Paulian Dumitrica  Leopold Krystyn  Richard Lein  Sigrid Missoni  Felix Schlagintweit 《International Journal of Earth Sciences》2008,97(4):865-881

The Mirdita Ophiolite Zone in Albania is associated with widespread mélanges containing components of up to nappe-size. We dated matrix and components of the mélange by radiolarians, conodonts, and other taxa. The components consist of radiolarites, pelagic limestones and shallow-water limestones, all of Triassic age, as well as ophiolites. Triassic radiolarite as a primary cover of ophiolite material proves Middle Triassic onset of Mirdita ocean-floor formation. The mélange contains a turbiditic radiolarite-rich matrix (“radiolaritic flysch”), dated as Late Bajocian to Early Oxfordian. It formed as a synorogenic sediment during west-directed thrusting of ophiolite and sediment-cover nappes representing ocean floor and underplated fragments of the western continental margin. The tectonic structures formed during these orogenic events (“Younger Kimmeridian or Eohellenic Orogeny”) are sealed by Late Jurassic platform carbonates. The geological history conforms with that of the Inner Dinarides and adjoining areas; we therefore correlate the Mirdita-Pindos Ophiolite Zone with the Vardar Zone and explain its present position by far-distance west-directed thrusting.  相似文献   

Application of FLATModel, a 2D finite volume code, to debris flows in the northeastern part of the Iberian Peninsula   总被引：7，自引：3，他引：4  

Vicente Medina  Marcel Hürlimann  Allen Bateman 《Landslides》2008,5(1):127-142

FLATModel is a two-dimensional shallow-water approximation code with corrections and modifications that create a simulation tool adapted to debris-flows behaviour. FLATModel uses the finite volume method with the numerical implementation of the Godunov scheme and includes correction terms regarding the effect of flow over high slopes and curvature. Additionally, the stop-and-go phenomenon, the basal entrainment and a correction regarding the front inclination of the final deposit are incorporated into FLATModel. In addition, different flow resistance laws were integrated in the numerical code including Bingham, Herschel–Bulkley and Voellmy fluid model. Firstly, our numerical model was validated using analytical solutions of a dam-break scenario and published data on a laboratory experiment. Secondly, three real events, which occurred in the northeastern part of the Iberian Peninsula, were back-calculated. Although field observations of the three events are not very detailed, the back-analyses revealed interesting patterns on the flow dynamics, and the numerical results generally showed good agreement with field data. Comparing the different flow resistance laws, the Voellmy fluid model presents the best behaviour regarding both the flow behaviour and the deposit characteristics. Preliminary simulation runs incorporating the effect of basal entrainment offered satisfactory results, although the final volume is rather sensitive on the selected friction angle of channel-bed material. The outcomes regarding the correction of the calculated front inclination of the final deposit showed that this implementation strongly improves the simulation results and better represents steep fronts of final deposits.  相似文献   

The Glarus thrust: excursion guide and report of a field trip of the Swiss Tectonic Studies Group (Swiss Geological Society, 14.–16. 09. 2006)     

Marco Herwegh  Jean-Pierre Hürzeler  O. Adrian Pfiffner  Stefan M. Schmid  Rainer Abart  Andreas Ebert 《Swiss Journal of Geoscience》2008,101(2):323-340

This excursion guide results form a field trip to the Glarus nappe complex organized by the Swiss Tectonic Studies Group in 2006. The aim of the excursion was to discuss old and recent concepts related to the evolution of the Glarus thrust. The major aspects were (i) the interplay between deformation, fluid flow and geochemical alteration, (ii) episodic versus continuous deformation and fluid flow, and (iii) the link between large-scale structures, microstructures, and geochemical aspects. Despite 150 years of research in the Glarus nappe complex and the new results discussed during the excursion, there exist controversies that still are unsolved.  相似文献   

Provenance of the Bosnian Flysch     

Tamás Mikes  Dominik Christ  Rüdiger Petri  István Dunkl  Dirk Frei  Mária Báldi-Beke  Joachim Reitner  Klaus Wemmer  Hazim Hrvatović  Hilmar von Eynatten 《Swiss Journal of Geoscience》2008,101(1):31-54

Sandwiched between the Adriatic Carbonate Platform and the Dinaride Ophiolite Zone, the Bosnian Flysch forms a c. 3000 m thick, intensely folded stack of Upper Jurassic to Cretaceous mixed carbonate and siliciclastic sediments in the Dinarides. New petrographic, heavy mineral, zircon U/Pb and fission-track data as well as biostratigraphic evidence allow us to reconstruct the palaeogeology of the source areas of the Bosnian Flysch basin in late Mesozoic times. Middle Jurassic intraoceanic subduction of the Neotethys was shortly followed by exhumation of the overriding oceanic plate. Trench sedimentation was controlled by a dual sediment supply from the sub-ophiolitic high-grade metamorphic soles and from the distal continental margin of the Adriatic plate. Following obduction onto Adria, from the Jurassic–Cretaceous transition onwards a vast clastic wedge (Vranduk Formation) was developed in front of the leading edge, fed by continental basement units of Adria that experienced Early Cretaceous synsedimentary cooling, by the overlying ophiolitic thrust sheets and by redeposited elements of coeval Urgonian facies reefs grown on the thrust wedge complex. Following mid-Cretaceous deformation and thermal overprint of the Vranduk Formation, the depozone migrated further towards SW and received increasing amounts of redeposited carbonate detritus released from the Adriatic Carbonate Platform margin (Ugar Formation). Subordinate siliciclastic source components indicate changing source rocks on the upper plate, with ophiolites becoming subordinate. The zone of the continental basement previously affected by the Late Jurassic–Early Cretaceous thermal imprint has been removed; instead, the basement mostly supplied detritus with a wide range of pre-Jurassic cooling ages. However, a c. 80 Ma, largely synsedimentary cooling event is also recorded by the Ugar Formation, that contrasts the predominantly Early Cretaceous cooling of the Adriatic basement and suggests, at least locally, a fast exhumation.  相似文献